Electronics circuit design-BJT

[kmdineshece]

what is difference between re model and hybrid model?

what is meant by small signal analysis?

How 180 phase shift happens in CE amplifier?

 

[Y.SAI SARASWATHI]

What do you mean by re model?
small signal analysis is analyzing BJT characteristics with input having low amplitude values sometimes especially at low frequencies.

 

[LvW]

In CE configuration output is collected at collector terminal,charge carriers take some time to travel from input to output terminal(equals 180 phase shift)

Please, convince yourself before answering.

Explanation for the phase inversion:
Increase in signal input voltage (Vbe increase) causes increase of collector current Ic.
As a consequence, the voltage drop across the collector resitor Rc (Vsupply-Vcoll.) increases.
Because Vsupply is constant the voltage at the collector Vc decreases.
This explains the phase inversion between input and output.

 

[crutschow]

As LvW noted, time has nothing to do with a CE configuration phase shift (if we are talking about its phase inversion).

 

[Y.SAI SARASWATHI]

Please, convince yourself before answering.

Explanation for the phase inversion:
Increase in signal input voltage (Vbe increase) causes increase of collector current Ic.
As a consequence, the voltage drop across the collector resitor Rc (Vsupply-Vcoll.) increases.
Because Vsupply is constant the voltage at the collector Vc decreases.
This explains the phase inversion between input and output.

SORRY that i have explained it in wrong way, i will not repeat this again(actually in micro wave range phase shift is because of this delay ,i was mistaken in interpreting it)